Fraction of galaxies with z_spec within the highest probability density confidence interval as a function of the confidence level before (left) and after (right) the contrast correction of the zPDF. Galaxies are grouped by their r-band flux in bins of 0.5 magnitudes. The diagonal line marks the (c) = c relation that is expected if the zPDF represents the actual redshift uncertainty. Values above (below) this line imply under- (over-)confidence in the z_best estimate.